In general, most switching power supplies used as power supplies of electronic equipment have employed capacitor input type rectifier circuits. Since a pulse-type input current is generated due to the capacitor and pulse-type input currents are simultaneously generated at the inputs of electronic, information and communication equipment, the pulse-type input current is provided to a power distribution line so that a harmonic distortion occurs in a power supply system and the power factor of a commercial power source is decreased.
To solve the problems, studies for a boost-type PFC (Power Factor Correction) control circuit having a function of correcting a power factor have been actively performed.
FIG. 1 is a view illustrating a boost converter type power supply device according to the related art.
Referring to FIG. 1, a power supply device 1 according to the related art includes a rectifier 2 having both terminals connected to an input power source, an inductor 3 connected between the rectifier 2 and a switching device 4 as an energy storage device, a diode connected between the switching device 4 and a capacitor.
The power source device 1 amplifies a voltage of an input side at a ratio to output an amplified voltage.
In 3-phase power system, when a high voltage such as a line voltage is applied to the power source device 1, a very high voltage is applied to an output end 5. Thus, since a voltage stress of a semiconductor device in the output end is increased, as a switching device, an IGBT (Insulated Gate Bipolar Transistor) device is used rather than a FET (Field Effect Transistor) device. Accordingly, there is a drawback that a low-frequency frequency must be used for the IGBT device. In addition, there are limitations in designing a power source device due to increases in the size and costs of a passive device.